A: Tonsillitis is an infection and swelling of the tonsils, often causing a severe sore throat, fever, earache, loss of voice, bad breath, fatigue, swollen lymph glands, and a white, gray, or yellowish coating on the tonsils. How it's treated depends on whether the infection is bacterial or viral. To determine the cause of the infection, your pediatrician will likely test for strep throat (a bacterial infection that's common in kids) by taking a swab of the back of your child's throat; you usually get results within a few minutes. If that test is negative but your doctor still suspects strep, she'll do another throat culture, which usually takes one to two days for results. If strep bacteria are found to be the culprit, your child will be prescribed antibiotics. But if your doctor thinks the cause is viral, all you can do is make your child comfortable and let the illness run its course. Acetaminophen or ibuprofen can help bring the fever down, and giving your child warm soup or tea can help soothe her throat. You can also show your child how to gargle with tepid salt water (most children 3 and older can do it).